Table 3.

Predictors of staying quit among those who made quit attempts (n=979^{^})

Factors	n	% Stay quit	Crude OR	95% CI	Adjusted OR	95% CI
Factors	n	% Stay quit	City				^***	^*
Beijing	163	23.3	Ref		Ref
Shenyang	177	9.0	.33	.17–.61^***	.41	.20–.83^*
Shanghai	93	24.7	1.08	.59–1.96	1.22	.63–2.40
Changsha	182	26.9	1.21	.74–1.98	1.40	.78–2.52
Guangzhou	139	25.2	1.11	.65–1.88	1.30	.71–2.38
Yinchuan	225	22.7	.96	.59–1.56	1.23	.68–2.24
Age at recruitment				^***		^**
18–39	170	12.9	Ref		Ref
40–54	432	18.3	1.51	.90–2.51	2.11	1.16–3.84^*
55+	377	29.4	2.81	1.70–4.63^***	3.21	1.74–5.89^***
Sex				NS		NS
Female	58	27.6	Ref		Ref
Male	921	21.3	.71	.39–1.29	.94	.44–2.01
Education				^**		NS
Low	158	31.6	Ref		Ref
Medium	629	19.4	.52	.35–.77^**	.69	.42–1.14
High	192	20.8	.57	.35–.92^*	.56	.29–1.05
Ethnicity	NS			NS		NS
Others	71	14.1	Ref		Ref
Han	908	22.2	1.75	.88–3.47	1.71	.76–3.92
Income				NS		NS
Low	214	18.7	Ref		Ref
Moderate	465	23.4	1.33	.89–1.99	1.75	1.08–2.84^*
High	235	22.6	1.27	.80–2.01	1.45	.81–2.62
Don’t know	65	15.4	.79	.37–1.69	.79	.32–1.91
Longest time quit				^***		^**
Never tried	284	19.4	Ref		Ref
Less than 1 month	285	14.4	.70	.45–1.09	.67	.37–1.19
1–6 months	262	22.1	1.18	.78–1.79	.97	.58–1.64
>6 months	140	37.9	2.54	1.62–3.98^***	1.97	1.16–3.39^*
Tried to quit within last year				NS		NS
Yes tried	304	20.4	Ref		Ref
Not tried	659	21.7	1.08	.77–1.51	.96	.61–1.51
Daily/weekly smokers				^***		NS
Daily smoker	883	19.9	Ref		Ref
Weekly smoker	96	37.5	2.41	1.55–3.76^***	1.47	.79–2.73
Cigarettes per day				^*		NS
<=10 CPD	397	26.7	Ref		Ref
11–20 CPD	441	17.9	.59	.43–.83^**	.93	.61–1.40
21–30 CPD	66	16.7	.55	.28–1.09	.54	.22–1.26
31+ CPD	67	19.4	.66	.35–1.26	.74	.34–1.61
Time to first cigarette				NS		NS
61+ min/don’t know	408	25.7	Ref		Ref
31–60 min	135	21.5	.79	.49–1.26	.99	.57–1.71
6–30 min	205	17.1	.60	.39–.91^*	.61	.34–1.03
<=5 min	231	18.6	.66	.44–.98^*	.77	.47–1.29
Self efficacy				^***		^*
Not at all sure	262	17.6	Ref		Ref
Somewhat sure	287	13.6	.74	.46–1.17	.64	.36–1.13
Very sure	187	23.0	1.40	.88–2.24	1.08	.60–1.93
Extremely sure	191	34.0	2.42	1.57–3.75^***	1.61	.90–2.90
Don’t know	51	35.3	2.56	1.33–4.94^**	1.86	.85–4.03
Intention to quit				^***		^**
No intention	412	19.2	Ref		Ref
Beyond 6 months/don’t know	290	19.3	1.01	.68–1.48	1.07	.66–1.73
Within 6 months	105	17.1	.87	.49–1.53	1.06	.54–2.06
Within 1 month	167	34.1	2.18	1.46–3.27^***	2.44	1.38–4.32^**
Outcome expectancy				NS		NS
Not at all	125	24.0	Ref		Ref
Somewhat/don’t know	389	22.4	.91	.51–1.38	.79	.45–1.38
Very much	464	20.3	.81	.50–1.29	.89	.48–1.64
Worries about health				NS		NS
Not at all	242	20.7	Ref		Ref
Somewhat/don’t know	452	23.7	1.19	.81–1.74	1.48	.92–2.36
Very much	283	18.7	.89	.57–1.32	.96	.54–1.71
Enjoy smoking too much to quit				NS		NS
Other	493	22.3	Ref		Ref
Agree	486	21.0	.93	.68–1.25	1.24	.86–1.80
Overall opinion about smoking				NS		NS
Other	317	22.7	Ref		Ref
Negative	429	21.1	.97	.68–1.38	.82	.54–1.24
Very negative	233	19.3	.82	.54–1.25	.60	.34–1.05
Smoking restrictions at home				NS		NS
No home bans	838	21.2	Ref		Ref
Home bans	141	24.1	1.18	.77–1.79	.78	.47–1.29

^{^}

Note: “n” in multivariate analysis is slightly less due to missing cases.

Ref: reference value.

Significant at p<0.05;

^**

p<0.01;

^***

p<0.001

NS=not significant.